This changes the __output_buffer to a new structure. This improves the
performace of std::format, std::format_to, std::format_to_n, and
std::formatted_size.
Currently, the library-internal feature test macros are only defined if
the feature is not available, and always have the prefix
`_LIBCPP_HAS_NO_`. This patch changes that, so that they are always
defined and have the prefix `_LIBCPP_HAS_` instead. This changes the
canonical use of these macros to `#if _LIBCPP_HAS_FEATURE`, which means
that using an undefined macro (e.g. due to a missing include) is
diagnosed now. While this is rather unlikely currently, a similar change
in `<__configuration/availability.h>` caught a few bugs. This also
improves readability, since it removes the double-negation of `#ifndef
_LIBCPP_HAS_NO_FEATURE`.
The current patch only touches the macros defined in `<__config>`. If
people are happy with this approach, I'll make a follow-up PR to also
change the macros defined in `<__config_site>`.
This re-formats a few headers that had become out-of-sync with respect
to formatting since we ran clang-format on the whole codebase. There's
surprisingly few instances of it.
We recently noticed that the unwrap_iter.h file was pushing macros, but
it was pushing them again instead of popping them at the end of the
file. This led to libc++ basically swallowing any custom definition of
these macros in user code:
#define min HELLO
#include <algorithm>
// min is not HELLO anymore, it's not defined
While investigating this issue, I noticed that our push/pop pragmas were
actually entirely wrong too. Indeed, instead of pushing macros like
`move`, we'd push `move(int, int)` in the pragma, which is not a valid
macro name. As a result, we would not actually push macros like `move`
-- instead we'd simply undefine them. This led to the following code not
working:
#define move HELLO
#include <algorithm>
// move is not HELLO anymore
Fixing the pragma push/pop incantations led to a cascade of issues
because we use identifiers like `move` in a large number of places, and
all of these headers would now need to do the push/pop dance.
This patch fixes all these issues. First, it adds a check that we don't
swallow important names like min, max, move or refresh as explained
above. This is done by augmenting the existing
system_reserved_names.gen.py test to also check that the macros are what
we expect after including each header.
Second, it fixes the push/pop pragmas to work properly and adds missing
pragmas to all the files I could detect a failure in via the newly added
test.
rdar://121365472
This patch runs clang-format on all of libcxx/include and libcxx/src, in
accordance with the RFC discussed at [1]. Follow-up patches will format
the benchmarks, the test suite and remaining parts of the code. I'm
splitting this one into its own patch so the diff is a bit easier to
review.
This patch was generated with:
find libcxx/include libcxx/src -type f \
| grep -v 'module.modulemap.in' \
| grep -v 'CMakeLists.txt' \
| grep -v 'README.txt' \
| grep -v 'libcxx.imp' \
| grep -v '__config_site.in' \
| xargs clang-format -i
A Git merge driver is available in libcxx/utils/clang-format-merge-driver.sh
to help resolve merge and rebase issues across these formatting changes.
[1]: https://discourse.llvm.org/t/rfc-clang-formatting-all-of-libc-once-and-for-all
This change requires quite a number of changes in the tests; this is not
code I expect people to use in the wild. So I don't expect breakage for
users.
Implements:
- P2905R2 Runtime format strings, as a Defect Report
Improves both the compile-time and run-time errors.
At compile-time it does a bit more work to get more specific errors.
This could be done at run-time too, but that has a performance penalty.
Since it's expected most use-cases use format* instead of vformat* the
compile-time errors are more common.
For example when using
std::format_to("{:-c}", 42);
Before compile output would contain
std::__throw_format_error("The format-spec should consume the input or end with a '}'");
Now it contains
std::__throw_format_error("The format specifier does not allow the sign option");
Given a better indication the sign option is not allowed. Note the
output is still not user-friendly; C++ doesn't have good facilities to
generate nice messages from the library.
In general all messages have been reviewed and improved, using a more
consistent style and using less terms used in the standard. For example
format-spec -> format specifier
arg-id -> argument index
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D152624
<__format/format_functions.h> was using <string>, we need to bring the include back that was removed in D154122.
Reviewed By: Mordante, #libc
Differential Revision: https://reviews.llvm.org/D155116
I did a manual review after the post-review comments in D149543
Reviewed By: #libc, philnik, ldionne
Differential Revision: https://reviews.llvm.org/D154122
`__iterator/readable_traits.h` can't be used by itself, intantiating `iter_value_t` requires `__iterator/iterator_traits.h`. `readable_traits.h` can't include `iterator_traits.h` though because `iterator_traits.h` requires `readable_traits.h`.
Move `iter_value_t` to `__iterator/iterator_traits.h` so that both headers can work standalone.
Reviewed By: Mordante, #libc
Differential Revision: https://reviews.llvm.org/D153828
This work-around was for Clang 13 and older, which we no longer support.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D152175
This is an extension and only adds the functions that are a considered a
but when called and ignoring the result.
Drive-by sort all nodiscard extensions in the documentation.
Reviewed By: #libc, philnik
Differential Revision: https://reviews.llvm.org/D152097
The code has been quite ready for a while now and there are no more ABI
breaking papers. So this is a good time to mark the feature as stable.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D150802
The newer formatters for (tuple, vector<bool>::reference) specify the
formatter's parse and format member function. This signature is slightly
different from the signature for existing formatters. Adapt the existing
formatters to the new style.
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D150034
LWG3720 Restrict the valid types of arg-id for width and precision in
std-format-spec
Depends on D144325
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D144326
std::format is currently experimental, so there is technically no
deployment target requirement for it (since the only symbols required
for it are in `libc++experimental.a`).
However, some parts of std::format depend indirectly on the floating
point std::to_chars implementation, which does have deployment target
requirements.
This patch removes all the availability format for std::format and
updates the XFAILs in the tests to properly explain why they fail
on old deployment targets, when they do. It also changes a couple
of tests to avoid depending on floating-point std::to_chars when
it isn't fundamental to the test.
Finally, some tests are marked as XFAIL but I added a comment saying
TODO FMT This test should not require std::to_chars(floating-point)
These tests do not fundamentally depend on floating-point std::to_chars,
however they end up failing because calling std::format even without a
floating-point argument to format will end up requiring floating-point
std::to_chars. I believe this is an implementation artifact that could
be avoided in all cases where we know the format string at compile-time.
In the tests, I added the TODO comment only to the places where we could
do better and actually avoid relying on floating-point std::to_chars
because we know the format string at compile-time.
Differential Revision: https://reviews.llvm.org/D134598
This change is almost fully mechanical. The only interesting change is in `generate_feature_test_macro_components.py` to generate `_LIBCPP_STD_VER >=` instead. To avoid churn in the git-blame this commit should be added to the `.git-blame-ignore-revs` once committed.
Reviewed By: ldionne, var-const, #libc
Spies: jloser, libcxx-commits, arichardson, arphaman, wenlei
Differential Revision: https://reviews.llvm.org/D143962
The constexpr validation parsed parts of the format string that didn't
belong to the specific replacement field.
Fixes https://llvm.org/PR60536
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D143402
Our implementation of std::format assumed that string_view's iterators
were raw pointers in various places. If we want to introduce a checked
iterator in debug mode, that won't be true anymore. This patch removes
that assumption.
Differential Revision: https://reviews.llvm.org/D138795
Changes all unqualified calls to __throw_format_error to use a qualified
call.
Reviewed By: #libc, philnik
Differential Revision: https://reviews.llvm.org/D140038
The Standard specifies which types are stored in the basic_format_arg
"variant" and which types are stored as a handle. Libc++ stores
additional types in the "variant". During a reflector discussion
@jwakely mention this is user observable; visit_format_arg uses the type
instead of a handle as argument.
This optimization is useful and will probably be used for other small
types in the future. To be conferment the visitor creates a handle and
uses that as argument. There is a second visitor so the formatter can
still directly access the 128-bit integrals.
The test for the visitor and get has been made public too, there is no
reason not too. The 128-bit integral types are required by the Standard,
when they are available.
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D138052
This partly reverts D133535 and enables CTAD for more parts in format.
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D135292
There are a handful of standard library types that are intended
to support CTAD but don't need any explicit deduction guides to
do so.
This patch adds a dummy deduction guide to those types to suppress
-Wctad-maybe-unsupported (which gets emitted in user code).
This is a re-application of the original patch by Eric Fiselier in
fcd549a7d828 which had been reverted due to reasons lost at this point.
I also added the macro to a few more types. Reviving this patch was
prompted by the discussion on https://llvm.org/D133425.
Differential Revision: https://reviews.llvm.org/D133535